Twist tube for false-twist device



Nov. 4, 1969 J. RASCHLE 3,475,895

TWIST TUBE FOR FALSE-TWIST DEVICE Filed Jan. 14, 1969 INVENTOR. 0665 Easeme- United States Patent US. Cl. 57--77.3 6 Claims ABSTRACT OF THE DISCLOSURE Twist tube for yarn texturing false-twist devices wherein the tube has a pin extending transversely across the tube bore and the tube is bored transversely, the axis of the latter bore being slightly displaced relatively to the axis of the pin.

This invention relates to apparatus useful for texturing yarns, and more particularly, to twist tubes or spindles utilized in false-twist devices.

It is well known in the industry that yarn may be textured by a false-twist process wherein the yarn is advanced longitudinally through a twist tube or spindle and looped around a pin extending transversely of the tube axis or bore. The tube is rotated to impart a false-twist in the yarn advancing towards the tube; and the yarn thus twisted is treated as desired.

The development of false-twist apparatus has led to improvements which permit the realization of increasingly higher spindle or twist tube revolution speeds. These high speeds, which have reached the order of several hundred thousand revolutions per minute, enable the yarns being textured to be advanced more rapidly than previously through the twist tubes thus in turn to increase the overall production rate of the false-twist equipment. Since the twist tubes are rotated by surface contact with rotating discs, the diameters of the tubes have been reduced to a minimum in order to obtain a high drive disc to twist tube annular speed ratio.

As stated, it is known to form twist tubes with a pin positioned transversely of the longitudinal bore or axis of the tube, and to advance the yarn longitudinally through the bore and once around the pin. It is also known to fabricate a tube which, in order to facilitate threading of the yarn, has at one end, a forked head of a diameter somewhat larger than that of the main part of the tube; and a pin of hardened material, such as sapphire extends across the gap between the tines in the forked head. It has been found that at extremely high revolution speeds, the tines of the forked head of such tubes bend away from each other due to the high centrifugal forces. This condition generates an eccentricity which leads to destruction of the pin.

I have conceived by my invention a high speed spindle or twist tube which eliminates the foregoing difficulties and disadvantages while permitting ease of threading.

Essentially, my contribution comprises a twist tube having a longitudinal bore, a pin positioned to extend transversely relatively to the longitudinal axis of the bore, and a transverse bore crossing the pin and the axis of which is displaced relatively to the axis of the pin by a distance equal to a fraction of the thickness of the pin. I prefer that the diameter of the transverse bore be equal to that of the pin and that the axis of this bore be perpendicular to the axis of the pin.

It will be understood that the displacement of the transverse bore relatively to the pin may be towards either end of the tube; and for clarity, I would say that the 3,475,895 Patented Nov. 4, 1969 'ice transverse bore, since it passes through a tube is actually two aligned holes in opposite sides of the tube.

The invention will be better understood after reading the following detailed description of the presently preferred embodiments thereof with reference to the appended drawings in which:

FIG. 1 is an enlarged central vertical sectional view through the longitudinal axis of an end of a twist tube or spindle;

FIG. 2 is a cross-sectional view taken along the lines 22 of FIG. 1;

FIG. 3 is a view similar to FIG. 1 but taken at to the section of FIG. 1; and

FIG. 4 is a top plan view of the tube as shown in FIG. 3.

Referring now to FIGS. 1 to 4 in detail, there is shown a terminal portion 1 of a twist tube according to the present invention wherein a longitudinal bore 2 communicates with a counterbore 3 at the end of the tube.- A pin 4 is mounted in the counterbore 3 transversely to the longitudinal axis thereof, and it will be noted that the central part of the pin is necked down to a lesser diameter than that of its ends.

A transverse bore 6 passes through the tube 1 and is positioned so that its longitudinal axis 7 is displaced downwardly, as viewed, relatively to that of the pin 4, and these two axis are preferably perpendicular to each other.

By way of example, the twist tube 1 may have an outer diameter of the order of 2.5 mm., the bore 2 a diameter of the order of 0.5 mm., and the counterbore 3 a diameter of the order of 1.5 mm. The pin 4 may be approximately 1 mm. in diameter at its ends and approximately 0.7 mm. at its center. The transverse bore 6 is of substantially the same diameter as that of the ends of the pin; and the axis of the pin 4 and bore 6 may be displaced approximately 0.2 mm.

By means of the present construction, the yarn 8 may be easily threaded by winding same once around the pin 4, as shown in FIGS. 1 and 3, in spite of the very small size of the twist tube. A flexible needle or the like may be of assistance in threading.

From the foregoing description, it will be seen that I have contributed a simple twist tube which may be easily threaded and which is adapted for high speed operation without the ditficulties heretofore encountered in the case of forked tubes.

I believe that the construction and operation of my twist tube will now be understood, and that the advantages thereof will be fully appreciated by those persons skilled in the art.

What is claimed is:

1. A twist tube of the class described comprising a body having a longitudinal bore, a pin positioned to extend transversely relatively to the longitudinal axis of said bore, and a transverse bore crossing said pin, the longitudinal axis of said transverse bore being displaced relatively to the longitudinal axis of said pin by a distance less than the diameter of said pin.

2. A twist tube according to claim 1, wherein the diameter of said transverse bore is equal to that of said pin.

3. A twist tube according to claim 1, wherein the longitudinal axis of said transverse bore and pin cross at right angles to each other.

4. A twist tube according to claim 1, wherein said transverse bore and pin are located adjacent one end of said tube.

5. A twist tube according to claim 4, wherein said tube is counterbored adjacent one end thereof and said pin and transverse bore cross said counterbore.

6. A twist tube according to claim 1, wherein said pin 3 is of reduced diameter at its mid-portion and the diameter of said transverse bore is equal to that of the end portions of said pin.

References Cited UNITED STATES PATENTS 1/1957 Klein 5777.3

4 3,349,554 10/1967 Boutonnet 57-77.3 3,363,409 1/1968 Schwabe et a1. 5777.3

FOREIGN PATENTS 1,049,776 11/1966 Great Britain. 1,071,534 6/1967 Great Britain.

DONALD E. WATKINS, Primary Examiner 

